Outlook on the Web - Mailbox Clean-up

Hi kazoo60 

Once I have read all your question/ issues and I hardly believe that there is another solution.

Retention Policy and Retention Tags - > https://docs.microsoft.com/en-us/microsoft-365/compliance/retention-policies can be applied to SPO, Teams, etc

For example you can create Retention tag (Delete email after 2 years) and the end user can apply this to the targeted email(s) or you can create a Retention policy (which will contain retention tags you create), apply it from EXO directly to affected mailbox(es)

But my recommendation is to set up some clear limits for Retention Tags or Retention Policy as no one wants emails to sudden disappear.

If you have other question regarding Retention Tags/Policy please let me know.

Hope this helps!